They asked study participants to rate the "trustworthiness" of nearly 300 faces (they were shown people of many races, though only scores for blacks and whites were used in the analysis). Then participants played a trust-based economic-reward game. They were shown a photo of their supposed "partner" in the game, who was either black or white.

Overall, if people showed an unconscious bias toward whites, they were more likely to rate whites as trustworthy when asked, and more likely to risk more money with white partners. The same bias was true in the minority of participants who showed a pro-black bias.

OK, that’s not shocking, right? People who are unconsciously biased toward whites are going to be more likely to trust whites, and vice versa with those who prefer blacks. Not rocket science.

But Leslie Hausmann, assistant professor of medicine at the University of Pittsburgh, says the point is that people tend to be totally unaware of the forces driving their decisions. She says that implicit bias is "still something that a lot of people don't internalize within their own lives and behavior" and "there's a reluctance to admit that in our day-to-day lives."